Growth solution based

As compared with CVD growth, solution-based deposition is preferred for the following reasons (1) the low-temperamre process allows for deposition on the substrate, (2) easy upscaling to large areas, (3) and decreased cost without vacuum. Therefore, the solution-based method is an important method for further consideration. 

Klechkovskaya, N. N. Maslov, V. N. Muradov, M. B. 1989. Growth and structure of semiconducting films of CdS, ZnS, and solid solutions based on them, obtained by the mechanisms of chemisorption from solutions of electrolytes. Soviet Physics Crystallogr. 34 105-107. 

Solution-Liquid-Solid (SLS) growth of semiconductor nanowires by Wang etal. (2006). The synthesis proceeds by a solution-based catalysed growth mechanism in which nanometer-scale metallic droplets catalyse the decomposition of metallo-organic precursors and crystalline nanowire growth. 

Solution-based synthetic strategies for one-dimessional nano-structures by Wang and Li (2006). Recent progress in the solution-based routes to prepare onedimensional nano-structures are reviewed. The role of crystal structure in the determination of the growth behaviour of the nano-crystals is underlined. 

For their rich potential in various applications described in the previous section, the synthesis and assembly of various ZnO micro and nanostructures have been extensively explored using both gas-phase and solution-based approaches. The most commonly used gas-phase growth approaches for synthesizing ZnO structures at the nanometer and micrometer scale include physical vapor deposition (40, 41), pulsed laser deposition (42), chemical vapor deposition (43), metal-organic chemical vapor deposition (44), vapor-liquid-solid epitaxial mechanisms (24, 28, 29, 45), and epitaxial electrodeposition (46). In solution-based synthesis approaches, growth methods such as hydrothermal decomposition processes (47, 48) and homogeneous precipitation of ZnO in aqueous solutions (49-51) were pursued. 

Our aim was to fabricate a multilayer (sandwich) with PZT on either side and with a very thin NF layer in between. As an accurate tailoring of the mid layer thickness is very tough in solution-based growth techniques, the authors tried to reduce the thickness by lowering the sol concentration. 

During the early stages of reaction, solution-based analysis techniques (e.g., wet chemical tests, such as titrimetry or chromatography HPLC or GPC) may be used to determine the extent of network growth. However, when the cure reaches the gel stage, the reduction in solubility renders such methods ineffective, necessitating the use of more exotic, nonsolution-based... 

Typically, crystal habits predicted based on crystal chemistry alone are best compared with crystals grown from sublimation processes, or to solution-based systems where the solvent/impurity interactions are negligible. In fact, significant deviations from structure-based predictions are often best explained by such solvent and impurity interactions (Davey et al. 1992 Winn et al. 2000). There are significant efforts underway to understand such phenomena at the molecular level and to consequently predict the influences of solvent and impurities on crystal growth rates. This will be further highlighted in subsequent sections. 

One of the most important results of theoretical investigations of crystal growth has been the quantification of the effect of solvents on crystal interface structure. In particular, a key parameter, called the a-factor, has been developed from fundamental theories that allows identification of likely growth mechanisms based only on solute and solution properties. 

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